Bimodal cellular thermoplastic materials

Abstract

Improvements to foaming methods and the interbimodal cellular structures of the foams made therefrom are disclosed.

1. A cellular thermoplastic material, comprising an interbimodal cellular structure comprising:
 a primary structure comprising primary cells having an average size of less than 2 μm, wherein the primary structure comprises the majority of the cellular thermoplastic material; and 
 secondary cells having an average size of 2 μm to 100 μm interspersed among the primary structure, wherein the secondary cells comprise cell walls; and wherein the inner cell walls of the secondary cells have nano-sized cells, wherein the nano-sized cells are segmented sections of the inner cell walls and have an average size of 0.1 nm to 500 nm. 
 
     
     
       2. The cellular thermoplastic material of  claim 1 , wherein the primary structure comprises cells having an average size of less than 1 μm, and the secondary cells have an average size of 2 μm to 3 μm. 
     
     
       3. The cellular thermoplastic material of  claim 1 , wherein the primary structure comprises cells having an average size of 1 μm to 2 μm, and the secondary cells have an average size of 10 μm to 15 μm. 
     
     
       4. The cellular thermoplastic material of  claim 1 , wherein the primary structure comprises cells having an average size of 0.1 nm to 100 nm, and the secondary cells have an average size of 2 μm to 100 μm.